Retaining height regulation

ABSTRACT

A method and regulating device for regulating the retaining height of tobacco in a retaining duct. The method includes determining the retaining height with at least one sensor, and controlling tobacco throughput of a conveyor organ connected to the retaining duct in the conveyor direction of the tobacco depending on the determined retaining height. The instant abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119 of German Patent Application No. 10 2005 013 077.1, filed on Mar. 18, 2005, the disclosure of which is expressly incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a method for regulating the retaining height of tobacco in a retaining duct, a method for assembling at least two tobacco rods as well as a retaining height regulating device and an arrangement for assembling at least two tobacco rods in a cigarette rod maker.

2. Discussion of Background Information

A respective arrangement for assembling at least two tobacco rods in a cigarette rod maker and a method for assembling at least two tobacco rods in a cigarette rod maker are known from the applicant's EP 1 364 588 A1.

Furthermore, EP 1 454 542 A1 discloses a method and a device by which a distributor element that distributes tobacco from a single tobacco supply into the two retaining ducts can be switched depending on the tobacco level in two retaining ducts.

SUMMARY OF THE INVENTION

The present invention provides a method and a device by which the tobacco level or the retaining height of the tobacco in at least one retaining duct of a distributor or a tobacco rod maker, in particular with two or more retaining ducts, can be regulated efficiently.

According to the method for regulating the retaining height of tobacco in a retaining duct, the retaining height is determined by at least one sensor, and the tobacco throughput of a conveyor organ connected to the retaining duct in the conveyor direction of the tobacco is controlled depending on the retaining height determined.

It has been discovered according to the invention that not only the flow of tobacco or the amount of tobacco per time unit into the retaining duct is relevant for regulating the retaining height of tobacco in a retaining duct, but that conveying the tobacco out of the retaining duct is at least just as relevant. By determining the tobacco level or the retaining height of the tobacco in the retaining duct and correspondingly controlling the tobacco throughput of a conveyor organ connected to the retaining duct, it is possible to regulate the retaining height of tobacco in a retaining duct in an easy, efficient and cost-effective manner and in particular set at an essentially constant height, so that a consistent conveyance of tobacco from the retaining duct to the customary suction rod conveyors is rendered possible, whereby a uniform tobacco rod assembly can be realized.

The inflow into the retaining ducts can be continuous, but it can be an interrupted inflow as well. In the case of the interrupted inflow, it makes sense to more strongly weight the integral part in the regulator, which can, e.g., be a PID regulator.

Preferably, the tobacco throughput is decreased when the retaining height falls below a predeterminable value. Furthermore, the tobacco throughput is preferably increased when the retaining height rises above a predeterminable value.

The tobacco throughput is expediently varied in a range of 10%, in particular 1% to 3%, around a predeterminable standard throughput. A variation of this type is sufficient for the filling fluctuations of the retaining duct to be expected.

A faster regulation is rendered possible if the extent of the variation is changed according to the retaining height. Hereby, for instance, not just the information is provided by a sensor that, e.g., the maximum retaining height has been reached in order to then increase the throughput in a sort of step function, but a continuous determination of the retaining height is rendered possible and the throughput of the conveyor organ is continuously changed accordingly. In this way, a linear relationship between the measured retaining height and the tobacco throughput through the conveyor organ can be provided, or a different relationship. A corresponding delay, which may be predeterminable, can be provided as well, i.e., that when the retaining height increases, the throughput is increased only after a delay of, e.g., a fraction of a second or up to several seconds.

It is provided according to the invention to further develop a method for assembling at least two tobacco rods from a single tobacco supply, whereby at least two retaining ducts are charged in particular directly with the tobacco from the tobacco supply. In this regard, the tobacco is fed from the at least two retaining ducts in the direction of at least two suction rod conveyors, in which the retaining ducts are arranged crosswise to the conveyor direction of the suction rod conveyors. The method for regulating the retaining height of the tobacco is used that has been described above according to the invention and preferably.

This method renders it possible to simultaneously produce at least two very homogeneous tobacco rods. For instance, it is possible that according to EP 1 364 588 A1 one of the retaining ducts described therein is preferably filled with tobacco, e.g., with a throughput that is conveyed into the respective retaining duct by 1% to 2% more than the other retaining duct. In this case it might happen that one of the two retaining ducts according to the above-referenced document is completely filled and that the other is essentially emptied. In order to counteract this, the retaining height can be correspondingly regulated according to the invention so that an essentially equal height of the two or more retaining ducts is the result. A very uniform rod assembly of each rod is thus rendered possible. It is also irrelevant for the uniform rod assembly that a different amount of tobacco is conveyed onto the respective suction rod conveyors, since the variation can be disregarded in comparison to the excess of tobacco usually conveyed onto the suction rod conveyor. It has to be taken into account that usually more than 10% of tobacco is conveyed to the suction rod conveyors in the excess and that this excess is cut off or removed from the tobacco rod before rod formation.

Preferably, the tobacco is conveyed from the at least two retaining ducts onto respectively at least one flow surface and subsequently fed to the at least two suction rod conveyors.

Preferably, the method for regulating the retaining height of the tobacco is applied to each retaining duct.

Preferably, the retaining ducts are filled alternately.

It is possible to predetermine the filling frequency and/or the respective filling duration of the retaining ducts. If the filling duration of the respective retaining ducts is set depending on the throughput of the conveyor organs connected to the retaining ducts, it is possible to produce very homogeneous tobacco rods.

Preferably, the conveyor organs are removal rolls. In a particularly simple manner it is possible to compare the rotational speeds of the removal rolls in order to control the filling duration.

If the filling duration of the respective retaining duct is set depending on the respective retaining height in the retaining ducts, a very exact regulation is rendered possible.

Further, a retaining height regulating device includes at least one sensor for determining the tobacco retaining height in a retaining duct and with a control and/or regulating device, such that the tobacco throughput of a conveyor organ that is connected to the retaining duct downstream in the tobacco conveyor direction can be controlled by the control and/or regulating device.

The retaining height regulating device according to the invention renders possible a very efficient regulation of the tobacco retaining height in a retaining duct, whereby a very uniform tobacco rod can be produced.

Preferably, the conveyor organ is a removal roll. A particularly simple regulation is rendered possible if the rotational speed of the removal roll can be controlled.

Moreover, an arrangement for assembling at least two tobacco rods in a cigarette rod maker includes a feed device, for conveying in particular measured and/or sifted tobacco to at least respectively one suction rod conveyor, composed of at least two retaining ducts and an above-described retaining height regulating device according to the invention is provided. Preferably, at least two flow surfaces are provided which guide the tobacco to the respective suction rod conveyors.

Preferably, the retaining ducts are arranged one behind the other crosswise to the conveyor direction of the suction rod conveyors. In this case, a very space-saving arrangement can be realized.

Preferably, a charging device is provided, which renders possible an alternate filling with tobacco of the at least two retaining ducts. A particularly exact regulation is possible if the respective duration of the charging of the respective retaining duct can be controlled.

The present invention is directed to a method for regulating the retaining height of tobacco in a retaining duct. The method includes determining the retaining height with at least one sensor, and controlling tobacco throughput of a conveyor organ connected to the retaining duct in the conveyor direction of the tobacco depending on the determined retaining height.

According to a feature of the invention, the controlling may include decreasing tobacco throughput when the determined retaining height falls below a predeterminable value.

In accordance with another feature of the present invention, the controlling may include increasing tobacco throughput when the determined retaining height rises above a predeterminable value.

Further, the controlling of the tobacco throughput can be varied in a range of 10% around a predeterminable standard throughput, and preferably, the tobacco throughput can be varied in a range of 1% to 3% around a predeterminable standard throughput. Moreover, an extent to which the tobacco throughput can be varied corresponds to the determined retaining height.

The invention is directed to a method for assembling at least two tobacco rods from a single tobacco supply. The method includes charging at least two retaining ducts with tobacco from the tobacco supply, conveying the tobacco from the at least two retaining ducts in the direction of at least two suction rod conveyors, in which the retaining ducts are arranged crosswise to a conveyor direction of the suction rod conveyors, and regulating the retaining height of the tobacco in accordance with the above-described method.

According to a feature of the instant invention, the tobacco from the at least two retaining ducts may be conveyed onto at least one flow surface and subsequently fed to the at least two suction rod conveyors.

In accordance with another feature of the invention, the retaining height of the tobacco may be regulated for each retaining duct.

According to still another feature, the retaining ducts can be filled alternately.

Further, at least one of a filling frequency and a filling duration of the retaining ducts can be predetermined. The predetermined filling duration of a respective retaining duct may be set depending on the throughput of the conveyor organs connected to the respective retaining ducts. Still further, the conveyor organs can be removal rolls, and rotational speeds of the removal rolls may be compared in order to control the filling duration. The predetermined filling duration of a respective retaining duct can be set depending on the retaining height in the respective retaining duct.

The present invention is directed to a retaining height regulation device that includes a retaining duct, a conveyor organ arranged downstream of, relative to a tobacco conveyor direction, and coupled to the retaining duct, at least one sensor for determining a tobacco retaining height in the retaining duct, and a control and/or regulating device structured and arranged to control a tobacco throughput of the conveyor organ.

In accordance with a feature of the present invention, the conveyor organ may be a removal roll. Further, a rotational speed of the removal roll can be controllable.

The present invention is directed to an arrangement for assembling at least two tobacco rods in a cigarette rod maker. The arrangement includes at least one suction conveyor, feed devices, composed of at least two retaining ducts, for conveying a product to the at least one suction rod conveyor, and a retaining height regulating device as discussed above.

According to the instant invention, the product may include at least one of measured and sifted tobacco

Further, at least two flow surfaces may be arranged to guide the tobacco to a respective one of the at least one suction rod conveyor.

According to another feature of the invention, the retaining ducts may be arranged one behind the other crosswise to the conveyor direction of the at least one suction rod conveyor.

In accordance with still yet another feature of the present invention, a charging device can be structured and arranged to alternately fill the at least two retaining ducts with tobacco. Moreover, a respective duration for filling a respective retaining duct is controllable.

Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is further described in the detailed description which follows, wherein:

The FIGURE illustrates a diagrammatic representation of an arrangement according to the invention for assembling at least two tobacco rods.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.

In a diagrammatic representation, the FIGURE shows an arrangement according to the invention for assembling at least two tobacco rods. In particular, essential parts of a tobacco distributor 10 are represented. Moreover, reference is made to European Patent Application No. EP 1 364 588 A1, the disclosure of which is expressly incorporated by reference herein in its entirety, in which many features or elements depicted in the FIGURE corresponds to FIG. 2 of EP 1 364 588 A1. It is further noted that the exemplary embodiments presented in EP 1 364 588 A1 can varied by one ordinarily skilled in the art in accordance with the teachings and disclosure of the instant invention without departing from the spirit and scope of the invention. Moreover, the present invention is not limited to the specific features of the FIGURE, such that certain features may be replaced with corresponding elements from EP 1 364 588 A1 without departing from the spirit and scope of the invention. In this regard, it is further noted that, while distributor element 39 depicted in the FIGURE is shown as a moveable flap, distributor element 39 may also be embodied or formed in accordance with FIGS. 1 and 4-11 of EP 1 364 588 A1. Moreover, instead of producing merely two tobacco rods, as shown in the FIGURE, it is contemplated that more than merely two tobacco rods, e.g., four tobacco rods, as described in EP 1 364 588 A1, can be produced in accordance with the invention.

In the distributor 10, sifted tobacco or unsifted tobacco, such as, e.g., kretek, is conveyed upward in a per se customary manner from the tobacco supply 80 by a steep conveyor 17 past a paddle roll 18 combing off excess tobacco, and is released into a drop duct 52. The impeller wheel 38, into which the tobacco falls, serves to portion and/or separate any transport air. The impeller wheel 38 releases tobacco into a drop duct 70 which is connected to a distributor element 39 in the conveyor direction downstream of the drop duct 70. The distributor element 39 is embodied or formed, as depicted in FIG., as a type of moveable flap such that which tobacco 28, 28′ is alternately admitted into the retaining ducts 40 and 40′ through movement of this moveable flap. Several other distributor elements 39 can also be provided, such as, e.g., those described in EP 1 364 588 A1. It is also possible to provide a distributor element 39 as described, e.g., in EP 1 454 542 A1, the disclosure of which is expressly incorporated by reference herein in its entirety.

In the retaining ducts 40 and 40′, tobacco 28 or 28′ is retained up to a retaining height 27 and 27′ or a corresponding tobacco level. The retained tobacco 28 or 28′ is removed from the retaining ducts 40 and 40′ by a removal roll 42 or 42′ and beaten out of the removal rolls 42, 42′ by a picker roller 41 or 41′. The tobacco then falls in the direction of a respective flow surface 44 or 44′. On the way there, the tobacco is conveyed by an air flow 43 or 43′ onto the flow surfaces 44, 44′ and to corresponding suction rod conveyors 50 or 50′ in a rod assembly unit 51. Tobacco rods 90 and 90′ are then formed on the suction rod conveyors 50 and 50′. The tobacco rods 90, 90′ generally comprise more tobacco than is necessary to produce an endless rod of uniform density. Therefore, excess tobacco is sheared off or cut off in the customary manner shortly before the casing of the respective tobacco rods 90, 90′. The excess customarily amounts to more than 10%. The tobacco rod is produced, e.g., in the conveyor direction 91 or the suction rod conveyors 50 and 50′ move in the conveyor direction 91.

In order to produce a tobacco rod that is as uniform as possible, in particular with regard to its density, it is desirable to produce the most uniform tobacco flow possible on the flow surfaces 44, 44′, which can also be referred to as fluidized beds. This is realized very well particularly when the retaining height 27, 27′ of the tobacco 28, 28′ is as constant as possible in the respective retaining duct 40, 40′. A further element for increasing the quality of the assembled tobacco rods is the vibrating element 60 or 60′ located respectively in the exit area of the retaining ducts 40, 40′. The retaining ducts 40, 40′, which are arranged essentially perpendicular, end with their duct outlets, which are embodied as vibrating duct outlets with corresponding vibrating elements 60, 60′, at the lower end respectively above removal roll 42, 42′ interacting with a picker roller 41, 41′. With regard to the function and embodiment of the vibrating elements 60, 60′ (sometimes referred to as vibrating retaining duct sections), reference is made to the applicant's EP 0 919 143 A1 and/or DE 197 52 717 A1. the disclosures of which are expressly incorporated by reference herein in their entireties.

In order to keep the retaining height 27, 27′ in the respective retaining ducts 40, 40′ as constant as possible, the retaining ducts 40, 40′ are filled as consistently as possible with a predeterminable charging frequency of the retaining ducts 40, 40′ and a corresponding predeterminable charging duration, which can be predeterminable, e.g., directly via a machine control device 23. Hereby it may occur on account of the respective geometry of the devices, in particular the device according to the FIGURE, that one of the retaining ducts 40, 40′ is filled with more tobacco than the other. In order to compensate for this, the invention proposes to adjust the throughput of tobacco from the retaining ducts 40, 40′ depending on the retaining height 27, 27′ through variation of the rotational speed of the removal rolls 42, 42′. To this end, sensors 11-16 are connected to a regulator 22 via cables 20, 21.

The regulator 22 is connected to the machine control device 23 via a cable 24. Signals can be transmitted both from the regulator 22 to the machine control device 23, as well as vice versa. The regulator 22 receives the signals collected by the sensors 11-16 and converts them into a regulating signal, by which the rotational speed of the removal rolls 42, 42′ is controlled. Removal rolls 42, 42′ are connected to the regulator via cables 25 and 26. This results in a regulation of the filling height or retaining height 27, 27′ of the tobacco 28, 28′ in the retaining ducts 40, 40′. The regulator can be, e.g., a customary PID regulator, the parameters of which can be set by one skilled in the art by simple trial and error.

As has been indicated above, it does not pose a problem that this regulation of the retaining height 27, 27′ of tobacco 28, 28′ in the retaining ducts 40, 40′ causes a tobacco rod 90, 90′ poured onto the respective suction rod conveyor 50, 50′ to feature overall a lower amount of tobacco than the other rod, since a certain amount of tobacco is cut off the tobacco rod in any case after pouring the respective tobacco rod. It should merely be ensured that the remaining and actually required amount of tobacco in the respective tobacco rod is also conveyed out of the respective retaining duct.

The sensors 11-16 can be simple sensors that merely indicate whether tobacco is present in the area of the respective sensors, e.g., ultrasonic sensors or visual sensors. Furthermore, the sensors can also be embodied to indicate a relatively exact status of the retaining height 27, 27′ in the respective retaining ducts 40, 40′, e.g., position-sensitive sensors, such as a CCD array. The exactness can hereby be in the range of a few millimeters. The regulating parameters should then be set depending on the type of sensors.

In addition to regulating the retaining height 27, 27′ via the tobacco flow discharged from the retaining ducts, it is also possible to control the tobacco flow that is guided into the retaining ducts. To this end, the distributor element 39 is to be controlled in a correspondingly variable manner as well, and not set to fixed, predetermined values. Hereby it is recommended to adapt in particular the charging duration of the respective retaining duct 40, 40′ to the retaining height 27, 27′. The lower the retaining height 27, 27′, the longer the charging duration should be.

Furthermore, it is possible to keep the retaining height 27, 27′ already at a relatively constant level through experience with the respective geometry on hand in that the charging duration of the respective retaining ducts is predetermined in a fixed manner for a different amount of time. This can be predetermined by fixed presettings, e.g., in the machine control device 23. The charging durations could then possibly also be varied manually if an unwanted change in the retaining height 27, 27′ occurs over a longer period of time. However, it still makes sense to regulate at least a fine adjustment of the retaining height 27, 27′ via the flow of tobacco from the retaining duct.

Furthermore, it is preferably provided that the mean value of the retaining height 27, 27′ and/or the total of the conveying rates or the tobacco flow of the removal rolls 42, 42′ serves to control the conveying rate of the steep conveyor 17.

The removal rolls 42, 42′ are preferably carded rolls, the cardings of which are tilted in particular in the rotary direction of the rolls.

It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.

List of Reference Numbers

-   10 Tobacco distributor -   11-16 Sensor element -   17 Steep conveyor -   18 Paddle roll -   20 Cable -   21 Cable -   22 Regulator -   23 Machine control device -   24-26 Cable -   27,27′ Retaining height -   28,28′ Tobacco -   38 Impeller wheel -   39 Distributor element -   40,40′ Retaining duct -   41,41′ Picker roller -   42,42′ Removal roll -   43,43′ Air flow -   44,44′ Flow surface -   50,50′ Suction rod conveyor -   51 Rod assembly unit -   52 Drop duct -   60,60′ Vibrating element -   70 Drop duct -   80 Tobacco supply -   90,90′ Tobacco rod -   91 Conveyor direction 

1. A method for regulating the retaining height of tobacco in a retaining duct, comprising: determining the retaining height with at least one sensor; and controlling tobacco throughput of a conveyor organ connected to the retaining duct in the conveyor direction of the tobacco depending on the determined retaining height.
 2. The method in accordance with claim 1, wherein the controlling comprises decreasing tobacco throughput when the determined retaining height falls below a predeterminable value.
 3. The method in accordance with claim 1, wherein the controlling comprises increasing tobacco throughput when the determined retaining height rises above a predeterminable value.
 4. The method in accordance with claim 1, wherein the controlling of the tobacco throughput is varied in a range of 10% around a predeterminable standard throughput.
 5. The method in accordance with claim 4, wherein the tobacco throughput is varied in a range of 1% to 3% around a predeterminable standard throughput.
 6. The method in accordance with claim 4, wherein an extent to which the tobacco throughput is varied corresponds to the determined retaining height.
 7. A method for assembling at least two tobacco rods from a single tobacco supply, comprising: charging at least two retaining ducts with tobacco from the tobacco supply; conveying the tobacco from the at least two retaining ducts in the direction of at least two suction rod conveyors, in which the retaining ducts are arranged crosswise to a conveyor direction of the suction rod conveyors; and regulating the retaining height of the tobacco in accordance with claim
 1. 8. The method in accordance with claim 7, wherein the tobacco from the at least two retaining ducts is conveyed onto at least one flow surface and subsequently fed to the at least two suction rod conveyors.
 9. The method in accordance with claim 7, wherein the retaining height of the tobacco is regulated for each retaining duct.
 10. The method in accordance with claim 7, wherein the retaining ducts are filled alternately.
 11. The method in accordance with claim 7, wherein at least one of a filling frequency and a filling duration of the retaining ducts is predetermined.
 12. The method in accordance with claim 11, wherein the predetermined filling duration of a respective retaining duct is set depending on the throughput of the conveyor organs connected to the respective retaining ducts.
 13. The method in accordance with claim 12, wherein the conveyor organs are removal rolls.
 14. The method in accordance with claim 13, wherein rotational speeds of the removal rolls are compared in order to control the filling duration.
 15. The method in accordance with claim 11, wherein the predetermined filling duration of a respective retaining duct is set depending on the retaining height in the respective retaining duct.
 16. A retaining height regulation device comprising: a retaining duct; a conveyor organ arranged downstream of, relative to a tobacco conveyor direction, and coupled to the retaining duct; at least one sensor for determining a tobacco retaining height in the retaining duct; and a control and/or regulating device structured and arranged to control a tobacco throughput of the conveyor organ.
 17. The retaining height regulating device in accordance with claim 16, wherein the conveyor organ is a removal roll.
 18. The retaining height regulating device in accordance with claim 17, wherein a rotational speed of the removal roll is controllable.
 19. An arrangement for assembling at least two tobacco rods in a cigarette rod maker, comprising: at least one suction conveyor; feed devices, composed of at least two retaining ducts, for conveying a product to the at least one suction rod conveyor; and a retaining height regulating device in accordance with claim
 16. 20. The arrangement in accordance with claim 19, wherein the product comprises at least one of measured and sifted tobacco
 21. The arrangement in accordance with claim 19, further comprising at least two flow surfaces arranged to guide the tobacco to a respective one of the at least one suction rod conveyor.
 22. The arrangement in accordance with claim 19, wherein the retaining ducts are arranged one behind the other crosswise to the conveyor direction of the at least one suction rod conveyor.
 23. The arrangement in accordance with claim 19, further comprising a charging device structured and arranged to alternately fill the at least two retaining ducts with tobacco.
 24. The arrangement in accordance with claim 23, wherein a respective duration for filling a respective retaining duct is controllable. 